I think that the ability to judge a work of art in a technical sense, while perhaps useful in some very limited respects, is completely irrelevant in terms of being an authority on that work's value, or meaning.
For instance, note this:
It was taken by the hubble telescope, and it is technically at least as good (arguably many times better) as any landscape photograph that ansel adams ever took. If technical skill was all that was important, then, since all technical skill is is some sort of adherence to some specific set of guidelines for how a certain piece should be made, humans are destined to be overshadowed as artists by computers.
Good music makes you feel something interesting, that's it.
As for musical "experts" judging music based on their keenly attuned criteria, well, kenny g and trent reznor are both accomplished musicians, musical experts if you will. I imagine that their ideas of what constitutes good music would be rather divergent.